#include <bits/stdc++.h>

using namespace std;

int main() {
    int n, m;
    cin >> n >> m;
    for (int i = 0; i < n; i++) {
        string s;
        cin >> s;
        if (s.find("LOVE") != string::npos) {
            cout << "YES" << endl;
            return 0;
        }
    }
    cout << "NO" << endl;
}